1. Field of the Invention
The present invention generally relates to a connector for connecting a relatively thin metallic or resinous pipe or tube which has a diameter less than about 20 mm and which is mounted in an automobile, machine, apparatus, or the like to supply oil or air.
2. Description of the Prior Art
A conventional connector of this kind is shown in FIG. 9. The body of the connector is indicated by numeral 21. The body 21 of the connector has a support wall portion 21' at its rear end. A socket body 22 has a pair of resilient claw walls 23 which are inclined forwardly. The socket body 22 is provided with a hole extending axially through the body 22. The claw walls 23 protrude from the wall defining this hole and are located in the front of the socket body 22 as viewed in the direction of insertion of the socket body. The claw walls 23 have annular peripheral wall portions 23' at their rear ends. The annular wall portions 23' have stepped portions 24. A pipe P.sub.o having an annular swelling wall portion P.sub.o ' is inserted in the socket body 22 in such a way that the claw walls 23 are pressed against the swelling wall portion P.sub.o ' and that the stepped portions 24 engage the support wall portion 21'. In this way, the pipe P.sub.o is connected.
In this prior art structure, when the pipe P.sub.o is connected, the socket body 22 is inserted. At this time, the claw walls 23 are brought into engagement with the pipe P.sub.o with a snap. Because of this structure, socket body 22 must have a large diameter. The stepped portions 24 formed on the annular peripheral wall portions 23' in the rear of the socket body form shoulder portions, which in turn constitute a protruding annular wall portion 24'. When the stepped portions 24 are brought into engagement with the support wall portion 21', the annular protruding wall portion 24' is pushed inwardly and crushed to permit the pipe to pass inside the support wall portion 21'. Again, the socket body 22 must have a large diameter. Accordingly, the whole assembly including the connector body 21 is made larger in size. This makes it difficult to install the assembly in a narrow space. In addition, the large diameter makes the claw walls 23 long. As a result, the socket body is brought into resilient contact with the swelling wall portion P.sub.o ' of the pipe P.sub.o with a smaller force. Also, permanent set in fatigue is produced. When vibration is kept applied to the socket for a long term, looseness occurs in the axial direction, thus deteriorating the airtightness. This will induce leakage, make the connection unstable, or introduce other problems.